You have some counters.
You put them into groups of three, and there is one counter left over. If you put the same counters into groups of four, there are three counters left over.
A) How many counters could you have? 19, 31, 43, 55
B) How many different ways can you find to do this? One way I solve it is by adding 12
C) How many counters might you have had if the total number of counters was more than 50? 55, 67, 79, 91, 103. It could go on forever.